Do rivers ever dry up?

Some rivers have a lifetime of many thousands of years, but they eventually dry up. As a river flows over land, the water wears away, or erodes, the rock of the riverbed. Over time, the river levels out the land until it is flat, and then it stops flowing. Rivers also need a steady source of water, such as from a mountain’s rainwater or snowmelt, or from rainfall. Without it, they will dry up.